Failure to file, etc. is a crime.
Zoomer: To answer your question, if you earn over the exemption amount you are required by law to file a return and pay the tax. If you do not, you are guilty of a misdemeanor, and, in additions to civil penalties and interest for nonpayment and nonfiling, you are subject to a fine of not more than $25,000, or imprisoned not more than 1 year, or both, together with the costs of prosecution. The IRS does not always prosecute a failure to file, but nevertheless, it is a crime.
The exemption amounts for filing returns for 2000 tax years are $12,950 for married filing joint return, $13,800 for married filing joint return with one spouse age 65 or over, $14,650 for married filing joint return with both spouses age 65 or over, $2,800 for married filing separate return, $10,150 for surviving spouse, $11,000 for surviving spouse age 65 or over, $9,250 for head of household, $10,350 for head of household age 65 or over, $7,200 for unmarried, and $8,300 for unmarried age.
WARNING: ONCE AGAIN Crager34 is giving bad advice.
Here is the applicable statutory law:
Amendment XVI of the US CONSTITUTION: The Congress shall have power to lay and collect taxes on incomes, from whatever source derived, without apportionment among the several States, and without regard to any census or enumeration.
SEC. 6012. PERSONS REQUIRED TO MAKE RETURNS OF INCOME.
6012(a) GENERAL RULE.--
Returns with respect to income taxes under subtitle A shall be made by the following:
6012(a)(1)(A) Every individual having for the taxable year gross income which equals or exceeds the exemption amount, except that a return shall not be required of an individual—
6012(a)(1)(A)(i) who is not married (determined by applying section 7703 ), is not a surviving spouse (as defined in section 2(a) ), is not a head of a household (as defined in section 2(b) ), and for the taxable year has gross income of less than the sum of the exemption amount plus the basic standard deduction applicable to such an individual,
6012(a)(1)(A)(ii) who is a head of a household (as so defined) and for the taxable year has gross income of less than the sum of the exemption amount plus the basic standard deduction applicable to such an individual,
6012(a)(1)(A)(iii) who is a surviving spouse (as so defined) and for the taxable year has gross income of less than the sum of the exemption amount plus the basic standard deduction applicable to such an individual, or
6012(a)(1)(A)(iv) who is entitled to make a joint return and whose gross income, when combined with the gross income of his spouse, is, for the taxable year, less than the sum of twice the exemption amount plus the basic standard deduction applicable to a joint return, but only if such individual and his spouse, at the close of the taxable year, had the same household as their home.
Clause (iv) shall not apply if for the taxable year such spouse makes a separate return or any other taxpayer is entitled to an exemption for such spouse under section 151(c) .
IRC SEC. 7203. WILLFUL FAILURE TO FILE RETURN, SUPPLY INFORMATION, OR PAY TAX: Any person required under this title to pay any estimated tax or tax, or required by this title or by regulations made under authority thereof to make a return, keep any records, or supply any information, who willfully fails to pay such estimated tax or tax, make such return, keep such records, or supply such information, at the time or times required by law or regulations, shall, in addition to other penalties provided by law, be guilty of a misdemeanor and, upon conviction thereof, shall be fined not more than $25,000 ($100,000 in the case of a corporation), or imprisoned not more than 1 year, or both, together with the costs of prosecution. In the case of any person with respect to whom there is a failure to pay any estimated tax, this section shall not apply to such person with respect to such failure if there is no addition to tax under section 6654 or 6655 with respect to such failure.
As to the constitutionality of the tax, see for example Guy S. Burroughs II and John W. Platt, Sr., Plaintiffs-Appellants v. Arthur E. Wallingford, Dora Nichols, R.D. Powell, Patrick Hayes, A.A. Muse, Jr., D.W. Cranford, Ruth Krebs, and Annette Rivera, Defendants-Appellees (CA-5), U.S. Court of Appeals, 5th Circuit, No. 85-2017, Summary Calendar, 1/13/86, 780 F2d 502, Affirming and remanding unreported District Court decisionThe constitutionality of income tax laws has been consistently upheld, Stites v. United States, 746 F.2d 1085 (5th Cir. 1984) (and cases cited). Additionally, the tax levy procedure in IRC §6331 does not violate due process.
